VLAN bridge interfaces are not getting IP assigned

[Dmitriy Rabotyagov]

By logic and documentation it is expected that agent will assign an IP address from the ARP_IPV4_PREFIX in ensure_arp_ndp_enabled_for_bridge function:
https://opendev.org/openstack/ovn-bgp-agent/blame/commit/4f8fe6adbfca242c5d4ef7d4d66b9240785f945e/ovn_bgp_agent/utils/linux_net.py#L137-L156

In docs it's stated:
https://docs.openstack.org/ovn-bgp-agent/latest/contributor/drivers/nb_bgp_mode_design.html#traffic-redirection-to-from-ovn
"If the provider network is a VLAN network, a VLAN device connected to the bridge is created, and it has ARP and NDP enabled."

However, `vlan_tag` is never being utilized and is simply ignored in the code. Thus, IP assignment happens only for the bridge itself and never for VLAN interfaces in that provider network.

With that passed parameter is not harmonized across the code. While some drivers pass it as a list:
https://opendev.org/openstack/ovn-bgp-agent/src/commit/4f8fe6adbfca242c5d4ef7d4d66b9240785f945e/ovn_bgp_agent/drivers/openstack/ovn_bgp_driver.py#L170-L172

https://opendev.org/openstack/ovn-bgp-agent/src/commit/4f8fe6adbfca242c5d4ef7d4d66b9240785f945e/ovn_bgp_agent/drivers/openstack/utils/wire.py#L66-L68

Other pass individual VLANs:
https://opendev.org/openstack/ovn-bgp-agent/src/commit/4f8fe6adbfca242c5d4ef7d4d66b9240785f945e/ovn_bgp_agent/drivers/openstack/utils/evpn.py#L228-L231

[Dmitriy Rabotyagov (noonedeadpunk)]

Also, this function will need some love regarding https://bugs.launchpad.net/ovn-bgp-agent/+bug/2054599 once it will start respecting vlans.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/ovn-bgp-agent/+/935801

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/ovn-bgp-agent/+/935801
Committed: https://opendev.org/openstack/ovn-bgp-agent/commit/fd029f985d913ae33290ae3c1bc8474a2aac1d1a
Submitter: "Zuul (22348)"
Branch: master

commit fd029f985d913ae33290ae3c1bc8474a2aac1d1a
Author: Dmitriy Rabotyagov <email address hidden>
Date: Wed Nov 20 16:06:18 2024 +0100

    Ensure that ARP/NDP is enabled for vlan devices

    In case VLAN networks are being used in neutron for providing external
    connectivity they will be assinged an IP address as well in order to
    get ARP/NDP proxying to work.

    With that VRF exposure method was relying on broken behaviour, as it
    never needed/expected ARP/NDP to be enabled var a vlan rather then bridge
    as well as vlan device to exist at all. So skipping vlan_id for evpn makes
    sense in this case, as only offload is important.

    Closes-Bug: #2088558
    Change-Id: Ibffda84801150a18ee8c441b4396afc900d8bc36

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/ovn-bgp-agent 5.0.0.0rc1 Flamingo release candidate.